Bug Description

[rationale]
DESKTOP_SESSION isn't properly set when using the "default" session (no parameter passed to Xsession), this leads to gconf not loading the custom unity settings, resulting in just nautilus being running.

The fix adds an Xsession.d script to both ltsp-client-core and ltsp-server, this script parses the parameter of Xsession and sets DESKTOP_SESSION to the expected value, similar to what lightdm does on a regular desktop.

3) in the past would lead to a blank screen, with the fix, you get unity-3d.

[regression potential]
As far as I can tell, DESKTOP_SESSION is only used by gconf at the moment, so if the code fails, all we should get is more gconf weirdness, though I can hardly see how it could get any worse than not getting a desktop session.

Well, to be accurate, the fallback actually happens but it seems dependent on the hardware and not always happening.
My test hardware for non-3D stuff is a kvm virtual machine using the cirrus virtual graphic card and at least for this one, if I select Ubuntu I get redirected to an Ubuntu 2D session just fine. That's mostly why I didn't catch this earlier.

My guess is that something in nux's graphic capability check is failing causing some hardware (if not most) to be considered as ok for Ubuntu when it's really not (if only because compiz fails in 16bit mode). I'm hoping to get a fix in nux instead of LTSP as people tend to update their application server a lot more than they do their chroot.

Actually i have a similar problem with a fat clients on a 3D capable machine (intel i915 and nvdia).
After user login, i see empty screen without anything and default wallpaper. The right click is activate, and i can change default wallpaper or launch nautilus.

Manually selecting unity-2d works around the issue, i have full desktop with unity-2d.

Possible by-pass by add the next line in LTS.CONF
LDM_SESSION="gnome-session --session=ubuntu-2d"

I am also experiencing issues when I went from 11.10 to 12.04 LTS. We currently use fat-clients and I am getting just a wallpaper on new accounts, the previous 11.10 accounts login just fine. I'm hoping this will be fixed soon as this is a pretty big issue for me not being able to add new user accounts at the moment.

If this package fixes the bug for you, please change the bug tag from verification-needed to verification-done. If it does not, change the tag to verification-failed. In either case, details of your testing will help us make a better decision.

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